ADR in CSGO is short for Average Damage per Round. It refers to the average amount of damage that a player has dealt within a single match, in a series of matches, or a complete event. For example, let’s say a particular player has managed to achieve an ADR of 70 in one CSGO match. This means that the player dealt damage to the enemy team at an average rate of 70 units per round for that match.
ADR is a very useful metric when it comes to professional CSGO. It is an even better indication of a player’s performance than the number of total kills that a player has managed to get in a particular match. Pro CSGO players often use this metric to gauge their performance in a particular match or series of matches. For example, if a pro player has an ADR of 80 in a whole tournament of several matches it means that the player has managed to tag the enemy team with a total of 80 units for every round played in all matches of that tournament. However, since it is an average, it may not accurately gauge the player’s performance in each round or each match of a series of matches.
In CSGO, a player with an ADR of 100 for a particular match means that they are really good. It is because a single player has 100 total health points. Hence, an ADR of 100 means one enemy killed in every round.